KeepAlive On vs. KeepAlive Off

HTTP is stateless protocol which makes a connection to transfer a single file and closes it.
It is not very efficient.

keepalive provides a persistent connection which uses same TCP connection for HTTP conversation instead of opening a new connection for each new request.

KeepAlive disabled

• opens a new connection for each new request
• Impact : Takes longer time to open web pages and wastes server resources
• HTTP header used : connection: close

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KeepAlive enabled

• uses same TCP connection for HTTP conversation
• improves website speed ; Better user experience
• reduces CPU usage (for creating and closing multiple connections)
• uses more RAM as Apache waits for multiple requests
• HTTP header used : Connection: Keep-Alive

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